android studio developer return to previous fragment

#ANDROID STUDIO DEVELOPER RETURN TO PREVIOUS FRAGMENT ANDROID#

Instead, you’ll get a callback to onNewIntent() with the new Intent and any extras. This prevents multiple copies of the same Activity on the top of the back stack.

#ANDROID STUDIO DEVELOPER RETURN TO PREVIOUS FRAGMENT ANDROID#

Instead of creating a stack of multiple copies of the same Activity (which is less fun both from a memory pressure perspective and back button fatigue), your Activity can use launchMode=”singleTop” in the Android manifest or you can add Intent.FLAG_ACTIVITY_SINGLE_TOP to your Intent. One case where this is easy to avoid is when you are launching the same Activity you are currently on. Of course, the back button loses some of its luster when you need to press it 10+ times to get out where you are. In most cases, you should be using this default behavior.īefore you go running off and overriding onBackPressed() directly, there’s a few specific cases you might want to consider: Preventing back button fatigue Nothing special here, but nothing confusing either - these symmetric, consistent behavior serves as the defaults. Neat, startActivity() or addToBackStack() and the default back button behavior. This is the ‘app switcher’ of the Android world - here you’ll see your most recent tasks and be able to select one to bring it back into the foreground.

The overview button (formerly recents), takes you, as you might imagine, to the Overview screen. Learn more about process priorities and when your app can be killed in the ‘Who lives and who dies?’ blog post. Note: moving your task to the background does not kill your task (although the topmost activity is most certainly paused+stopped): it’ll live on until the process is killed.

The home button is probably the most straightforward with its single focus: it puts the current task into the background, taking you back to your launcher. Of course, the back button isn’t the only navigation button on a modern Android device (no we don’t talk about the menu button anymore).

Each transaction added to the back stack is reversed in turn until they’re all removed at which time the default activity finishing behavior again kicks in. This way when the back button is hit, the FragmentTransaction is reversed (an added fragment removed, a replaced fragment restored, or a removed fragment re-added). When you provide a fragment transaction to add, replace, or remove a fragment from your UI, you can use addToBackStack() to effectively add the FragmentTransaction to the back stack. The back stack doesn’t apply only to activities: it also applies to fragments. This repeats until there’s nothing left in the back stack and you’re back at the launcher. The back button (by default) then ‘pops’ the stack, calling finish() on the topmost activity, destroying it and removing it from the back stack and taking you back to the previous activity.

Android studio developer return to previous fragment